{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# [Lists](https://docs.python.org/3/library/stdtypes.html#lists)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "my_empty_list = []\n",
    "print('empty list: {}, type: {}'.format(my_empty_list, type(my_empty_list)))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "list_of_ints = [1, 2, 6, 7]\n",
    "list_of_misc = [0.2, 5, 'Python', 'is', 'still fun', '!']\n",
    "print('lengths: {} and {}'.format(len(list_of_ints), len(list_of_misc)))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Accessing values"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "my_list = ['Python', 'is', 'still', 'cool']\n",
    "print(my_list[0])\n",
    "print(my_list[3])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "coordinates = [[12.0, 13.3], [0.6, 18.0], [88.0, 1.1]]  # two dimensional\n",
    "print('first coordinate: {}'.format(coordinates[0]))\n",
    "print('second element of first coordinate: {}'.format(coordinates[0][1]))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Updating values"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "my_list = [0, 1, 2, 3, 4, 5]\n",
    "my_list[0] = 99\n",
    "print(my_list)\n",
    "\n",
    "# remove first value\n",
    "del my_list[0]\n",
    "print(my_list)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Checking if certain value is present in list"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "languages = ['Java', 'C++', 'Go', 'Python', 'JavaScript']\n",
    "if 'Python' in languages:\n",
    "    print('Python is there!')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "if 6 not in [1, 2, 3, 7]:\n",
    "    print('number 6 is not present')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## List are mutable"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "original = [1, 2, 3]\n",
    "modified = original\n",
    "modified[0] = 99\n",
    "print('original: {}, modified: {}'.format(original, modified))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "You can get around this by creating new `list`:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "original = [1, 2, 3]\n",
    "modified = list(original)  # Note list() \n",
    "# Alternatively, you can use copy method\n",
    "# modified = original.copy()\n",
    "modified[0] = 99\n",
    "print('original: {}, modified: {}'.format(original, modified))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## `list.append()`"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "my_list = [1]\n",
    "my_list.append('ham')\n",
    "print(my_list)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## `list.remove()`"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "my_list = ['Python', 'is', 'sometimes', 'fun']\n",
    "my_list.remove('sometimes')\n",
    "print(my_list)\n",
    "\n",
    "# If you are not sure that the value is in list, better to check first:\n",
    "if 'Java' in my_list:\n",
    "    my_list.remove('Java')\n",
    "else:\n",
    "    print('Java is not part of this story.')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## `list.sort()`"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "numbers = [8, 1, 6, 5, 10]\n",
    "numbers.sort()\n",
    "print('numbers: {}'.format(numbers))\n",
    "\n",
    "numbers.sort(reverse=True)\n",
    "print('numbers reversed: {}'.format(numbers))\n",
    "\n",
    "words = ['this', 'is', 'a', 'list', 'of', 'words']\n",
    "words.sort()\n",
    "print('words: {}'.format(words))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## `sorted(list)`\n",
    "While `list.sort()` sorts the list in-place, `sorted(list)` returns a new list and leaves the original untouched:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "numbers = [8, 1, 6, 5, 10]\n",
    "sorted_numbers = sorted(numbers)\n",
    "print('numbers: {}, sorted: {}'.format(numbers, sorted_numbers))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## `list.extend()`"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "first_list = ['beef', 'ham']\n",
    "second_list = ['potatoes',1 ,3]\n",
    "first_list.extend(second_list)\n",
    "print('first: {}, second: {}'.format(first_list, second_list))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Alternatively you can also extend lists by summing them:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "first = [1, 2, 3]\n",
    "second = [4, 5]\n",
    "first += second  # same as: first = first + second\n",
    "print('first: {}'.format(first))\n",
    "\n",
    "# If you need a new list\n",
    "summed = first + second\n",
    "print('summed: {}'.format(summed))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## `list.reverse()`"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "my_list = ['a', 'b', 'ham']\n",
    "my_list.reverse()\n",
    "print(my_list)"
   ]
  }
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